Monoolefinic alcohols have potential value in the production of alkyl-substituted conjugated dienes, such as isoprene. A convenient method of producing monoolefinic alcohols is to react an olefin such as isobutylene with an aldehyde. The aldehydes are readily produced by the oxidative treatment of a lower alcohol with a molecular oxygen-containing gas such as air.
However, a limiting factor in the feasibility of the process has been the difficulty in extracting the aldehyde from the reaction mixture resulting from the alcohol oxidation step. The oxidation step reaction product mixture contains unreacted alcohol, aldehyde, and water, and tends to form various close boiling admixtures or even azeotropic admixtures in some instances. Separation by conventional means, such as by fractional distillation, is difficult, expensive, or commercially impractical. Efforts to separate the aldehyde by treatment with an extraneous solvent have been helpful, but have necessitated the use of an additional and expensive material which always poses the likelihood of product contamination and interference in desired reactions since some of the extraneous solvent tends to recycle.